[foresto]

I think the Samsung Galaxy S10e and some of the Google Pixel models are nearly hand-size, but I don't know of any that rival the (now unsupported) Xperia XZ1 Compact. The XZ2 Compact is (AFAIK) still supported by LineageOS, but it's chunky.

I have read rumors that a new Xperia Compact model is likely within the next year. I don't want to get my hopes up too high, because this is unconfirmed and because the definition of "compact" seems to be expanding over the years, but I am optimistic.

I doubt that we'll ever see the likes of the Xperia Mini Pro again.

Edit: Here's a handy phone size comparison tool: https://www.phonearena.com/phones/size